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BACKGROUND OF THE INVENTION
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Field of the invention
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The
The invention relates to a sheet processing apparatus which is detachable on the main assembly of a
Image recording device
such as B. a copier
or a printer is attached and an image recording device that with
equipped with such a sheet processing device. In a special way
the present invention relates to a sheet processing apparatus,
the bows
reliable
expel
and an image recording apparatus equipped with such a sheet processing apparatus.
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State of the art
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In
Recently, sheet processing equipment such. B. sorter for
Sorting bows,
on which images have been formed as optional devices
for image recording devices such. B.
electrophotographic copiers
or laser printer has been developed. This type of processing equipment is
meant for,
with the bows at least
to carry out a processing
such as B. sorting, stapling or Bogenglattrütteln.
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One
Sheet processing apparatus,
which has a stapler for stapling sheets, is such
designed that the
Stapling process performed
after being transported in the construction of the sheet processing machine
Bows to it
be brought, arranged in the interior of the structure transport career
to go through and then stacked on a post-processing tray
become.
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The
Sheet processing apparatus
for stapling a pile of sheets
is used to make bows in
to arrange a stack on the post-processing tray and moves
a stapler that serves as a stapler to stapling
at one or more positions (typically two
Positions). While
stapling process, it is not possible
the bows
for the
next
Position the task on the postprocessing tray. consequently
it is necessary for
the stapling operations
on a job-by-job basis between the bowgroup intervals
set.
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However, the intervals between the sheets cause a decrease in productivity. In other words, the number of sheets processed per unit time decreases. An in
31 The sheet processing apparatus shown has been proposed as a sheet processing apparatus which avoids such a reduction in productivity (see, for example, Document
JP-H9-48545 ).
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This in 31 shown conventional sheet processing apparatus 10 has a buffer roll path 14 on that in a transportation career 12 halfway through the sheet transport career to a post-processing tray 11 is arranged. In the buffer roll path 14 The sheets are wrapped around a rotary buffer roll 13 wrapped so that they before transport to the post-processing tray 11 be kept in a waiting state.
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With the structure described above, in the conventional sheet processing apparatus 10 Bows taken from one in the main assembly of an image recorder 15 angeordne th Bogenausstoßwalzenpaar 17 transported in the buffer roll path 14 placed so that a group of sheets on the buffer roller 13 is stored for postprocessing 11 is transported after the processing, such. Stapling, the previous group on the post-processing tray 11 has been completed and the previous group from the postprocessing tray 11 has been ejected by a rotating upper roller 18a an oscillating pair of rollers 18 The bows interact with the lower roller 18b holds. As a result, the intervals between the sheets are not lengthened during the stapling operation, so that a decrease in productivity can be avoided.
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With the provision of the buffer roller track 14 suffers this conventional sheet processing device 10 However, with the problem that it is necessary, an installation space for the buffer roll 13 and the buffer roller track 14 set up to interrupt the transport of the subsequent sheets for post-processing shelf 11 so as to keep them in a waiting state during the stapling operation, thereby increasing the size and cost of the sheet processing apparatus.
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Moreover, in the prior art sheet processing apparatus 10 , because the arches with the help of Oszillationswalzenpaars 18 are ejected, the sheet transport rate change due to a fluctuation in friction between the upper roller 18a and the lower roller 18b or due to a fluctuation in its rotational speed, so that a displacement between the upper portion of the sheets and the lower portion of the sheets may occur. Therefore, the sheet discharge operation is not uniform, and a fluctuation of the time required for discharging the sheets occurs.
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Furthermore, even those from the documents
US-B-6264189 and
US-A-5605323 known conventional sheet processing apparatus, which were adapted to the stored in a buffer path sheet on the post-processing tray After the sheets have been ejected on the finishing tray, they do not meet the latest requirements for increasing the processing speed, so that a device having a reduced processing time has been demanded.
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SUMMARY OF THE INVENTION
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It
It is the object of the present invention to provide a sheet processing apparatus which
reliable
Can eject bows.
Another object of the present invention is to provide an image recording apparatus
that improved productivity
and equipped with a sheet processing device that can discharge sheets evenly.
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According to the present
Invention for that
is determined to achieve the aforementioned object, a sheet processing apparatus is provided
that includes a sheet holding device for holding a plurality
supplied
Bows in
a stack, a first sheet stacking device, on the sheets, the
held by the sheet holding device or the sheet holding device
have crossed without being held, stacked and one
Processing, a second sheet stacking apparatus,
with respect to the sheet transport direction of the first sheet stacking apparatus
is arranged forward, on which sheets are to be stacked, a first
Sheet transport device for transporting on the first
Sheet stacking device stacked sheets to the sheets to
second sheet stacking device, and a second sheet transport device
for transportation
the stacked on the first Bogenstapelvorrich direction sheets in the direction
the second sheet stacking apparatus, wherein after that on the first sheet stacking apparatus
stacked bows
through the second sheet transport device in the direction of the second
Sheet stacking device were transported by a predetermined amount,
the first sheet transport device passing through the sheet holding device
held bows
and simultaneously transport the sheets stacked on the first sheet stacking apparatus
in a state in which a forward edge of the on
The first sheet stacking apparatus stacked on the bow
front side by a predetermined amount sticking out over the
forward edge of the sheets passing through the sheet holding device
held thereby to the on the first sheet stacking device
stacked bows
to eject the second sheet stacking device and the by the sheet holding device
held bows
to stack on the first sheet stacking device.
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In
the sheet processing device
according to the present
Invention, which is intended to achieve the aforementioned object,
the second sheet transport device can be adapted to be in relation to
the sheet transport direction is a trailing edge of the on the first sheet stacking device
stacked bows
to initiate,
in order by these bows
to transport.
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The
Sheet processing apparatus
according to the present
Invention, which is intended to achieve the aforementioned object,
can also be a control device for controlling the second
Have sheet transport device in such a way that the second
Sheet transport device on the first sheet pile device
stacked bows transported to
the forward edge of these arches on the forward facing
Side protrudes by a predetermined amount over the forward facing
Edge of the arches,
which are held by the sheet holding device.
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According to the present
Invention intended to achieve the above object,
There is also provided an image recording apparatus having
an image forming apparatus for forming an image on a
Sheet and a sheet processing apparatus for performing a
Processing a sheet on the image by the image forming apparatus
wherein the sheet processing apparatus is made of any of the above
mentioned
Sheet processing equipment
consists.
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The
Sheet processing apparatus
according to the present
Invention is constructed such that after the on the first
Sheet stacking apparatus stacked sheets through the second sheet transport device
by a predetermined amount in the direction of the second sheet stacking device
to get promoted,
the bows,
which are held by the sheet holding device and on
the first sheet stacking apparatus stacked sheets simultaneously through the first
Bow conveyor be transported to the second sheet stacking device
pushed out
to become. As a result, the overlapping area of the sheet pile becomes
and the buffer sheets
reduced by an amount corresponding to the predetermined transportation amount
the sheet stack corresponds, so that therefore the sheet stack reliable from
the buffer sheets
can be separated and for reliable stacking on the second
Sheet stacking device ejected
can be. additionally
can
the bows,
as they are carried by the first and second sheet transporter, fast
and ejected without fluctuations in sheet ejection time.
That's why it's possible to have one
Device with reduced processing time available
put.
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BRIEF DESCRIPTION OF THE DRAWINGS
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1 Fig. 12 is a schematic front cross-sectional view showing an image recording apparatus in the form of a copying machine with a sheet processing apparatus according to an embodiment of the present invention, which is arranged on the main component of the apparatus.
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2 is a block diagram of the in 1 shown copying machine.
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3 Fig. 12 is a schematic front cross-sectional view showing a sheet processing apparatus according to the embodiment of the present invention.
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4 Fig. 12 is a schematic front cross-sectional view showing various drive systems in the sheet processing apparatus according to the embodiment of the present invention.
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5 Fig. 10 is an enlarged view showing a main part of the sheet processing apparatus according to the embodiment of the present invention.
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6 is similar to 5 an enlarged view showing a state in which a trailing edge assistant has been moved.
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7 shows a state in which the trailing edge assistant of the in 6 shown state was moved further.
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8th is a block diagram of the control system of the in 3 shown sheet processing device.
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9 FIG. 10 is a flowchart illustrating a sheet stack discharge operation of the in 3 illustrated sheet processing device illustrated.
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10 FIG. 15 is a diagram illustrating the operation timing of the trailing edge assistant and the oscillation roller pair. FIG.
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11 FIG. 12 is a diagram illustrating the operation timing of the trailing edge assistant and an oscillation roller pair. FIG.
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12 FIG. 12 is a diagram illustrating the operation timing of the trailing edge assistant, the oscillation roller pair and a first sheet discharge roller pair. FIG.
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13A and 13B illustrate the operation of the sheet processing apparatus in the event that sheets do not need to be stored during sheet processing: 13A shows a state in which a first sheet has been delivered to the sheet processing apparatus; 13B shows a state in which a first sheet has been received.
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14A and 14B illustrate the operation of the sheet processing apparatus in the case that sheets do not need to be stored during the sheet processing and show states that the 13A and 13B following states follow: 14A shows a state in which the first sheet has passed through the first Ausstoßwalzenpaar; and 14B Fig. 12 shows a state in which the first sheet has been dropped in a manner to bridge a stack tray and a processing tray.
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15A and 15B illustrate the operation of the sheet processing apparatus in the event that sheets during the sheet processing do not need to be stored and show conditions that the in 14A and 14B following states follow: 15A shows a state in which the first sheet is conveyed to the processing tray; and 15B shows a state in which the first sheet is further transported to the processing tray.
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16A and 16B illustrate the operation of the sheet processing apparatus in the case that sheets do not need to be stored during the sheet processing and show states that the 15A and 15B following states follow: 16A shows a state in which the second sheet has been stored in the sheet processing apparatus; and 16B shows a state in which the first sheet abuts against a stop.
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17 FIG. 12 illustrates the operation of the sheet processing apparatus in the case where sheets need not be stored during sheet processing, and shows a state in which three sheets are stacked on the processing tray.
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18A and 18B illustrate the operation of the sheet processing apparatus in the event that sheets do not need to be stored during sheet processing and show conditions corresponding to those in 17 shown follow: 18A shows a state in which the ejection of the sheet stack from the processing tray to the stack tray has just begun; 18B shows a state in which the sheet stack has been ejected halfway from the processing tray to the stack tray.
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19 illustrates the operation of the sheet processing apparatus in the event that sheets during the Bogenverarbei device does not need to be stored and shows a state in which the Sheet stack has been ejected from the processing tray to the stack tray.
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20A and 20B illustrate the operation of the sheet processing apparatus in the event that sheets are stored during sheet processing: 20A shows a state in which the first sheet has been delivered to the sheet processing apparatus; and 20B shows a state in which the first sheet was taken up to a turning point.
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21A and 21B illustrate the operation of the sheet processing apparatus in the case that sheets are stored during the sheet processing and show states that the in 20A and 20B following states follow: 21A shows a state in which the trailing edge of the first sheet is received by a trailing edge receiving portion; and 21B shows a state in which the first sheet is pressed by a trailing edge retention against a lower transport guide plate.
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22A and 22B illustrate the operation of the sheet processing apparatus in the case that sheets are stored during the sheet processing and show states that the in 21A and 21B following states follow: 22A shows a state in which the second sheet has been conveyed into the sheet processing apparatus; and 22B Fig. 12 shows a state in which the second sheet has been fed further into the sheet processing apparatus.
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23A and 23B illustrate the operation of the sheet processing apparatus in the case that sheets are stored during the sheet processing and show states that the in 22A and 22B following states follow: 23A shows a state in which the second sheet was taken up to the turning point; 23B Fig. 10 shows a state in which the trailing edge of the second sheet is received by the trailing edge receiving portion.
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24 Fig. 10 illustrates the operation of the sheet processing apparatus in the case where sheets are stored during the sheet processing and shows a state in which the first and second sheets overlap each other and are pressed by a trailing edge restraint against a lower transport guide plate.
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25A and 25B illustrate the operation of the sheet processing apparatus in the case that sheets are stored during the sheet processing and show conditions that the in 24 shown state follow: 25A shows a state in which the third sheet was delivered; and 25B shows a state in which the third sheet has been completely delivered.
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26A and 26B illustrate the operation of the sheet processing apparatus in the case that sheets are stored during the sheet processing and show states that the in 25A and 25B following states follow: 26A shows a state in which the ejection of the sheet stack from the processing tray to the stack tray has just begun; and 26B shows a state in which the sheet stack is conveyed in the ejection direction. 27A and 27B illustrate the operation of the sheet processing apparatus in the case that sheets are stored during the sheet processing and show states that the in 26A and 26B following states follow: 27A shows a state in which the sheet stack has been ejected from the processing tray; and 27B shows a state in which the buffer sheets are conveyed to the processing tray.
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28A and 28B illustrate the operation of the sheet processing apparatus in the case that sheets are stored during the sheet processing and show states that the in 27A and 27B following states follow: 28A shows a state in which the buffer sheets are conveyed into the processing tray; and 28B shows a state in which the buffer sheets are conveyed further into the processing tray.
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29 Figure 11 illustrates the operation in the case where the protrusion length of the forward edge of the sheet stack is short beyond the forward edge of the buffer sheet.
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30 illustrates a problem that arises in the case when the sheet stack is ejected only by the pair of oscillating rollers.
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31 Fig. 16 is a front cross-sectional view showing a conventional sheet processing apparatus.
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DESCRIPTION OF THE PREFERRED
EMBODIMENTS
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Hereinafter, a sheet processing apparatus according to an embodiment of the present invention and a copying machine will be described as an example of an image recording apparatus equipped with the sheet processing apparatus, with reference to the accompanying drawings. In connection with this, it should be noted that the image recorder has a copying machine, a facsimile machine, a printer or a multifunction machine, the combined functions of these devices Therefore, therefore, the image recording apparatus to be provided with the sheet processing apparatus according to the present invention is not limited to a copying machine.
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The
following description of the embodiment
will be given with reference to a case where the sheet processing apparatus is an optional device
is that is designed to be removable as a single device
to be attached to the main component of an image recording apparatus. It is
but it is clear that that
Sheet processing apparatus
according to the present
Invention also for
the case can be applied in which the device with the
The image recording device
one piece
is trained. Even in this case, the functions differ
of the device
not those of the sheet processing machine described below
so that's why
the description of such a device
is omitted.
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1 Fig. 12 is a schematic cross-sectional view showing a copying machine to which a sheet processing apparatus is attached. In particular, the sheet processing device z. B. an end processing device.
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(Image recording device)
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The copier 100 is from a device main assembly 101 and a sheet processing apparatus 119 composed. In the upper part of the main assembly 101 is an original feeder 102 arranged. Sheets D are set by a user to an original fitting section 103 placed and individually a registration roller pair 105 supplied by means of a Zuführabschnitts 104 , The original D is then passed through the registration roller pair 105 temporarily stopped and caused to form a loop, so that an oblique feeding is corrected. The original D then passes through an introductory track 106 a reading posi tion 108 so that the image formed on the surface of the original D is read. After crossing the reading position 108 the original D passes through an ejection track 107 to put on a discharge tray 109 to be expelled.
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In the case where both the front and rear sides of the original are to be read, one page of the original D is read first when the original is the reading position 108 traverses in the manner described above. Then the original is forced, the ejection orbit 107 to traverse and by means of a reversing roller pair 110 to turn around, so again to registration roller pair 105 to be transported in a state in which the pages of the original have been turned over.
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Thus, skew feeding of the original D by the registration roller pair is corrected in the same manner as in the case where the image on one of the sides has been read, and the original is made to be the in-feed web 106 and the reading position 108 in which the image on the other side of the original D is read to traverse. Then the original D is initiated, the ejection track 107 to go through to the discharge tray 109 to be expelled.
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The picture on the original D, which is the reading position 108 passes through, is irradiated with light, that of a lighting system 111 is sent out. The light reflected from the original is reflected by a mirror 112 on an optical element 113 (composed of a CCD or other element) through which image data is generated. A laser beam based on this image data is applied to the image recording apparatus in the form of, for example, a photosensitive drum 114 directed so that a latent image is formed thereon. Alternatively, the device may be designed in such a way that the reflected light passes directly through the mirror 112 on the photosensitive drum 114 is directed to produce a lateness image, even if such a structure is not shown in the drawings.
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Toner supplied from a toner supply device (not shown) becomes the one on the photosensitive drum 114 formed image so that a toner image is formed. A cassette 115 preserves recording media in the form of paper sheets or Plasitkfilmen and so on. A bow is taken from the cassette 115 issued in response to a recording signal and by a registration roller pair 150 with appropriate timing between the photosensitive drum 114 and a transmission device 116 moved in. The toner image on the photosensitive drum 114 is through the transmission device 116 transferred to the bow. When the sheet on which the toner image has been transferred has a fixing device 117 through the toner image is fixed by heat and pressure, which passes through the fixing device 117 be supplied.
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In the event that images have to be formed on both sides of the recording medium, the one-sided sheet on which the image passes through the fixing device 117 was fixed, caused to run through a double-sided path, which in the forward position of the fixing device 117 is arranged, and between the photosensitive drum 114 and the transfer device 116 moved in. Thus, an image is also transferred to the back of the sheet. The toner image is in the fixing device 117 fixed and the bow is ejected to the outside (ie the finishing device 119 ).
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2 Fig. 10 is a block diagram showing an overall control system of the copying machine. The copier 100 as a whole, it is adapted to pass through a CPU circuit section 200 to be controlled. The CPU circuit section 200 has a ROM 202 , in which operations or control operations of various components are stored, and a RAM 203 in which various information should be temporarily stored as needed. An original feeder control section 204 is used to control the original feeding operation of the original feeder 102 heading. The image reading control section 205 is set up the lighting system 111 etc. to control the original reading. An image signal control section 206 has the task of reading information from the image reading control section 205 to receive or receive image information from an external computer 207 via an external I / F 208 were sent to process the information and a conditioned signal to a printer control section 209 to send. The printer control section 209 is provided for the photosensitive drum 114 etc. on the basis of the image signal control section 206 processed image signal so as to obtain an image generated on a sheet.
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An operating section 210 is adapted in such a way that the information about the sheet size and the information about what processing (for example stitching) is provided for the sheets, can be entered when a user uses the copier. In addition, the operating section 210 designed to display operating status or other information about the main assembly 101 of the copier or the finishing device 119 as a sheet post-processing device. A finishing processing control section 211 is there for the internal processing of the finishing device 119 to control as a sheet post-processing device. A fax control section 212 is provided for controlling the copying machine to allow the copier to function as a facsimile machine so that it can transmit a signal to another facsimile machine or receive it from another facsimile machine.
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(Sheet processing apparatus)
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3 shows a vertical cross-sectional view of the sheet processing apparatus. 4 shows a vertical cross-sectional view, in which a drive system is shown. 2 Fig. 10 is a block diagram of the control system of the sheet processing apparatus. 9 Fig. 10 is a flowchart for illustrating the operation of the sheet processing apparatus. 10 to 12 are diagrams showing the moving speed of a trailing edge assistant 134 and the sheet transport speed of an oscillation roller pair 127 in relation to the elapsed time show. 10 shows a single stack delivery sequence in which a sheet pile is traced by the trailing edge assistant 134 and the oscillation roller pair 127 is delivered. 11 shows a stack delivery control under the condition where the initial speed of the trailing edge assistant 134 from the initial speed of the oscillation roller pair 127 different. 12 shows a simultaneous stack delivery sequence in which a stack of sheets and buffer stock stored in a buffer unit simultaneously by the trailing edge assistant 134 , the oscillation roller pair 127 and a first transport roller pair are conveyed.
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The sheet processing device 119 has a function of binding the sheet stack. The sheet processing device 119 is equipped with stapler units 132 stapling a stack of sheets at positions near the edge of the sheet pile, one in 3 shown stapling device 138 for stapling the sheet pile at a middle position and a folding unit 139 for folding by the stapler 138 stapled sheet stack at the stapling position to bring the sheet pile into a book-like shape.
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The sheet processing apparatus according to the invention 119 has a buffer unit 140 for temporarily storing (ie buffering) a plurality of sheets which are in a straight (or planar) state during operation of the stapler units 132 are stacked.
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Because the buffer unit 140 is configured to store a plurality of sheets stacked in a straight state, the buffer unit 140 be formed in a planar shape, in contrast to conventional structures such. B. the structure of the in 31 shown buffer roll 13 contains. Consequently, it is possible to make the sheet processing apparatus compact and lightweight. Also, because the buffer unit 140 can save the sheets in a straight state and the sheets are not corrugated, unlike the case with the buffer roll, the handling of the sheets easily, so that the sheet processing time of the sheet processing apparatus can be reduced.
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The sheet processing device 119 is controlled by an in 2 and 8th shown finish processing control section 211 , In the CPU 221 the finishing processing control section 211 is a ROM 222 in which a control sequence stored in response to a command of the CPU circuit section is stored 200 the main assembly of the copier, and further a RAM 223 arranged, in which, if circumstances require, information required to control the sheet processing device are to be saved. In addition, the finishing processing control section is 211 with a sheet surface detection sensor 224 connected, which operates on the basis of the operation of a sheet surface detection lever to be described below. The CPU 221 is designed for the up and down movement of a stacking tray 128 based on a sheet detection signal of the sheet detector sensor 224 , The finishing processing control section 211 is designed to allow the operation of an input conveyor motor M2 due to the above procedure. control that for the rotation of an entry roller pair 121 , a buffer roller 124 and a first sheet discharge roller pair, and further configured to control the operation of a stack feed motor M3 for rotating the oscillation roller pair 127 and a reversing roller 130 and to operate (ie, enable / disable) the transmission of rotation from the stack feed motor M3 to the lower roller, and to operate a sub-staple clutch CL to turn it on and off 127b to control.
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Incidentally, the CPU control circuit section may 200 and the finishing processing control section 211 , as in 2 shown to be integrated.
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Because the bottom roller 127b and the reverse roll 130 Usually rotated by the stack feed motor M3 can, if a sheet or stack of sheets through the lower roller 127b and the reverse roll 130 when the sheet or sheet pile is crumpled or torn when slippage occurs or a difference in the transport speed between both rolls is generated. In the 4 shown sub-stacking clutch CL is intended to compensate for such a speed difference.
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(Description of the sheet pile stapling and
the ejection process)
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When a sheet stitching operation by a user via the display on the operating section 210 (shown in 2 ) of the copier 100 is selected, the CPU circuit section controls 200 Each section in the main assembly of the device to copy the copying machine 100 and sends a sheet-stitching operation signal to the finishing processing control section 211 ,
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The description of the operation with reference to 13A and 19 refers to a case where the CPU circuit section 200 on the basis of by the user in the operating section 210 inputted sheet size information, it is determined that the sheet is long (for example, in the case of an A3 sheet size) or a case in which it is determined based on the sheet type information that the sheet is a special sheet having characteristics other than a normal sheet differ, such. As a cardboard, a thin paper sheet, a label paper or a color paper sheet. In other words, the description of the operation in conjunction with the 13A and 19 to the case where the processing of the stack buffer sheets (which will be described later) is performed on a processing tray 129 is started after a sheet pile on the stack tray 128 is ejected, so that there is a case in which it is not necessary to temporarily store the sheets during the sheet processing. However, it will be understood that the operation described below may be performed regardless of the length of the sheet and whether the sheet is a special sheet or not.
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The finishing processing control section 211 activates the input conveyor motor M2 and the stack feed motor M3 on the basis of the sheet stitching operation signal. The finishing processing control section 211 also activates a Pufferwalzenennstößel SL1 (shown in 4 ) to the buffer roller 124 from a lower transport guide plate 123b and activates a ram, not shown in the drawing, around the top roller 127a of the oscillation roller pair 127 from the lower roller 127b keep. The activation and stopping of the input conveying motor M2 and the stack feeding motor M3 is controllable step by step in accordance with the movement of the sheets.
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The first of the ejection roller pair 120 the main assembly 101 of the copier 100 (shown in 1 ) delivered sheet is transported by a pair of pickup rollers 137 and through a flap 122 (both in 3 and 4 shown), so as to the entry roller pair 121 to be delivered. The pickup roller pair 137 is adapted to be rotated by a common conveying motor M1, which is also the abovementioned Ausstoßwalzenpaar 120 drives.
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As in 13A shown, the entry roller pair 121 through the input conveyor motor M2 (shown in FIG 4 ) turned to the first bow 21 to transport. The arc 21 becomes the first ejection roller pair 120 conveyed while passing through a guiding device 123 guided, which is composed of the upper transport guide plate 123a and the lower transport guide plate 123b ,
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The arc 21 will, as in 13B shown further transported by the rotation of the first Bogenausstoßwalzenpaares 126 and how 14A points towards the stacker 128 released. The arc 21 falls in a way that he is the stacker and the processing tray 129 bridged. After that, the top roller 127a lowered by the plunger, not shown in the drawings, so that the sheet 21 between the upper roller 127a and the lower roller 127b is held.
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At this time, have the top roller 127a and the bottom roller 127b through the stack feed motor M3 (shown in FIG 4 ) already turned in the respective direction indicated by arrows. In addition, the reverse roller is also 130 that with the processing tray 129 can be brought into contact and detached from it already by the stack feed motor M3 (shown in FIG 4 ) is rotated in the direction shown by an arrow. In conjunction with this, the transmission of driving force to the lower roller 127b during the processing of the first sheet by the operation of the sub-staple clutch CL (shown in FIG 4 ) is activated, but during the processing of the second sheet and the subsequent sheets, the transmission is interrupted, so that the lower roller 127b can rotate freely. That's because when the bottom roller 127b rotates, while the second or subsequent sheet after the first sheet on the processing tray 129 is dropped, there is a risk that the first sheet through the lower roller 127b against a stop 131 can be pressed and the first sheet can be crumpled.
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As in 16A As shown, the arc P1 slides by the rotation of the oscillation roller pair 127 and the reverse roller 130 on the processing tray 129 descending to the right in the direction indicated by an arrow. At this time, the trailing edge assistant is located 134 at its standby position. The upper roller 127a is released from the sheet P1 before the sheet P1 to the stop 131 abuts. The sheet P1 is through the reversing roller 130 brought to the stop 131 to rest. Thereafter, a sheet width alignment by a pair of alignment plates 144a and 144b (please refer 5 ) carried out.
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Subsequently, the subsequent sheets are processed in the same way on the processing tray 129 stored. As in 17 is shown when a predetermined number of sheets on the processing tray 129 is deposited, the pile of sheets through the stapling units 132 as in 3 and 4 stapled shown. Alternatively, punching may be applied to the sheet stack by a punching unit (not shown) instead of the stitching operation by the stapling units 132 ,
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Hereinafter, the operation of the sheet processing apparatus will be described with reference to the flowchart in FIG 9 described.
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As in 18A shown is the top roller 127a lowered by the plunger, which is not shown in the drawings, so that the sheet between the upper roller 127a and the lower roller 127b (S101) is held. Approximately 15 Milliseconds after (S103) the sub-staple clutch CL is operated (S102), the alignment plates become 144 withdrawn from the sheet pile (S104). Then the stack tray 128 moved to a position where they pass through the sheet surface detection lever 133 can be detected and remains in a position where it can easily receive the pile of sheets to be delivered (S105).
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As in 18B shown, the upper roller rotate 127a and the bottom roller 127b Holding the sheet stack P between them in the direction shown by arrows, while the trailing edge assistant 134 pushes the trailing edge of the sheet pile P. Thus, the sheet stack P on the stack tray 128 pushed out. The trailing edge assistant 134 is on a belt 142 arranged as in 5 to 7 shown moved backwards and forwards by a trailing edge auxiliary motor M4.
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In the operation described above, if as in 10 and 11 shown the activation time (T1) and the initial speed (132 mm / s) of the oscillation roller pair 127 and the trailing edge assistant 134 are the same size and at the same time (T2) they reach the same acceleration end speed (500 mm / s), the pair of oscillation rollers 127 and the trailing edge assistant 134 eject the sheet stack onto the stack of sheets without applying a pulling or pushing force (S106).
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As in 11 however, in some cases is the initial speed of the trailing edge assistant 134 (here assumed to be 300 mm / s) larger (under the above-mentioned assumption) than the initial speed of the oscillation roller pair 127 because of the straps 143 and 142 , the rotational force of the trailing edge auxiliary motor M4 to the trailing edge assistant 134 or transferred to other elements. In this case, the beginning of the movement of the trailing edge assistant 134 interrupted until the time T3, wherein the sheet transport speed of Oszillationswalzenpaares 127 300 mm / s achieved, and the movement of the trailing edge assistant 134 is initiated when the sheet transport speed of the oscillation roller pair 127 is reached. In particular, the movement of the trailing edge assistant becomes 134 at time ΔT = (T3 - T1) after the oscillation roller pair 127 was activated, started. In connection with this, in the case where the initial speed of the oscillation roller pair 127 is higher than the initial speed of the trailing edge assistant 134 , the activation time of the oscillation roller pair 127 in contrast delayed by ΔT. In the case that the initial speed of the oscillation roller pair 127 and the initial speed of the trailing edge assistant 134 are the same, ΔT is zero.
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With the difference .DELTA.T in the activation time, the oscillation roller pair 127 and the trailing edge assistant 134 eject the sheet stack without exerting a tensile or compressive force on the sheet stack even if there is a difference between the initial speeds of the oscillation roller pair 127 and the trailing edge assistant 134 is present. In addition, one on a roller track of Oszillationswalzenpaares 127 attributable to deterioration of the quality of the sheet pile or the quality of the images on the sheets in the stack can be avoided.
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The sheet discharge of the sheet stack in the direction of the stack tray 128 is through the oscillation roller pair 127 , the trailing edge assistant 134 and the reverse roll 130 started (S108). When the trailing edge assistant has been moved by about 15 mm (S109), it is returned to its original position (or its home position) (S110, the process of FIG 12 shown starting position storage control). The sheet pile becomes, as in 19 shown by the oscillation roller pair 127 on the stack tray 128 pushed out. Thereafter, the operation of the sheet stack discharge is completed at a time when the upper roll 127a of the oscillation roller pair 127 is separated from the lower roll (S111 and S112).
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Referring to 18B is the first sheet of the next pile of sheets to the entrance roller pair 121 when the ejection of a sheet stack has been started.
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In the sheet processing device 119 According to this embodiment, since the trailing edge assistant 134 for transporting the stack of sheets, the sheet pile is fed reliably, the sheet stack is reliably transported without damaging the surface of the sheet stack, unlike the case where the sheet stack is ejected by means of a rotating roller pressed against the surface of the sheet stack.
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(Description of the buffer work process)
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The
The above description is directed to the case where
For example, the transport interval between the sheets is so long
is that the stapling process
while
the next
Fed sheet
is for
executed a sheet pile
can be. On the other hand, the following description is for one
Buffering process in which the transport interval between
the bows
is short and if the subsequent bows during the stapling process for a
Sheet pile executed
will be delivered, the subsequent sheets during this stitching process
stored (that is, buffered).
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The sheet processing device 119 performs the buffering operation based on a buffering operation command by the finishing processing control section 211 when through the CPU circuit section 200 It is determined that an interval between that of the main assembly 101 of the copier 100 delivered sheets is shorter than the time required for the Bogenheftungsvorgang. In this case, the buffer roll becomes 124 by the plunger SL1 (shown in FIG 4 ) lowered to the lower transport guide plate 123b to get in touch.
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In the 20A and 20B It is assumed that a sheet stack on the processing tray 129 and the stapling operation for this stack of sheets by means of the Hefereinheiten 132 (shown in 3 and 4 ) is carried out.
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As in 20A is shown, when the first sheet P1 of the next sheet stack is delivered during the execution of the stapling operation for the sheet stack P on the processing tray 129 , the arch P1 through the entry roller pair 121 to the buffer roller 124 transported. The buffer roller 124 is detected by the input conveyor motor M2 (shown in FIG 4 ) to transport the sheet P1 downstream. At this time, the upper first sheet discharge roller pair becomes 126a of the first sheet discharge roller pair 126 from the lower first sheet discharge roller pair 126b kept away by a first Bogenausstoßwalzentrennstößel SL2 (see 4 ). It should be noted that the first sheet discharge nip plunger SL2 is not explicitly illustrated in FIG 4 as shown by the buffer ejection roller centering plunger SL1 in FIG 4 is covered. In addition, the top roller 127a of the oscillation roller pair 127 also from the lower roller 127b by the ram, which is not shown in the drawings, kept away.
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If the trailing edge of the arc P1 as in 20B shown, the reversal point SP reaches, the rotation of the buffer roller 124 turned over so that the arc P1 as in 21A shown, reversed to the rear. At substantially the same time becomes a trailing edge retention 135 from the lower transport guide plate 123b detached, so that a trailing edge receiving portion 136 is released. The device is designed to reduce the incidence to determine the arc P1 at the reversal point SP by measuring a predetermined time or counting the number of revolutions of the buffer roller after a supply path sensor S1 operating in the forward direction of the in 4 shown inlet roller pair 121 is arranged, is activated by the leading edge of the arc P1.
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After the forward edge of the bow 21 has been determined, the rearward edge portion of the arc P1 as in 21A shown by the trailing edge receiving portion 136 receive. After that, the trailing edge retention 135 brought back to the previous position, so that the sheet P1 by means of the at the trailing edge restraint 135 arranged friction element 141 against the lower transport guide plate 123b is pressed.
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Subsequently, the second arc P2 as in 22A shown delivered. The second sheet P2 passes through the entry roller pair 121 transported. At this time, it happens that the arc P2, the trailing edge retention 135 exceeds. Thereafter, the arc P2 as in 22B also shown by the buffer roller 124 transported.
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At this time, the first sheet will be 21 together with the second sheet P2 by means of the buffer roll 124 against the lower transport guide plate 123b pressed. As a result, the first sheet P1 is caused to follow the second sheet P2 in transit so as to move forward. The first bow 21 However, it is not really moved because it is at the rear edge retention 135 arranged friction element 141 against the lower transport guide plate 123b is pressed.
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The second arc P2 is also sent back when the trailing edge of the second arc P2, as in 23A . 23B and 24 shown in a similar manner as the first arc reaches the reversal point SP. Then the second arc P2 is made by means of the trailing edge restraint 135 arranged friction element 141 against the lower transport guide plate 123b pressed while he the first bow 21 overlaps.
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Subsequently, the third bow 23 fed and the trailing edge of the third arc 23 goes through, as in 25A shown, the entry roller pair 121 so that the first to third sheets are held between the lower first sheet discharge roller pair 126b and the upper first sheet discharge roller pair 126a that like in 25B shown serve as a retaining sheet transport section. In this state becomes the third bow 23 from the first and second bow a little in the front direction crazy. Since the stapling operation for the sheet stack P on the processing tray 129 is finished at this time, the trailing edge assistant 134 along the processing tray 129 moved to like in 26A shown to push up the trailing edge of the sheet pile P. Consequently, the forward edge Pa of the sheet stack P on the forward side projects beyond the forward edge P3a of the third sheet P3 having a length L.
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As in 26B shown is the top roller 127a also lowered and the three bows 21 , P2 and P3 are between the top roller 127a and the lower roller 127b held. In conjunction with this is the trailing edge retention 135 from the second arch 22 replaced the first bow 21 and the second bow 22 release.
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After that, the three bows 21 . 22 and P3 and the sheet stack P are transported while being held between the oscillation roller pair 127 , If the sheet pile is as in 27A and 27B shown on the stacker tray 128 ejected, the trailing edge of the first sheet P1 and the second sheet P2 comes from the first Bogenausstoßwalzenpaar 126 out and the rearward portion of the three sheets is through the processing tray 129 added.
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In the in 27B shown state, if as in 10 and 11 shown as the activation time (T1) and the initial speeds (132 mm / s) of the first sheet ejection roller pair 126 , the oscillation roller pair 127 and the rear edge assistant 134 are the same size and they reach the same acceleration end speed (500 mm / s) at the same time (T2), the first pair of sheet discharge rollers 126 , the oscillation roller pair 127 and the trailing edge assistant 134 eject the sheet stack onto the stack of sheets or the three sheets without applying a tensile or compressive force. However, in the case where there is a difference in the initial speeds, the sheet stack can be ejected without any tensile or pressing force applied to the sheet stack or the three sheets by setting a time difference for activating the above-mentioned portions in one Process S107 in the flowchart of FIG 9 similar way. In addition, one on a roller track of the first Bogenausstoßwalzenpaares 126 or the oscillation roller pair 127 attributable to deterioration of the quality of the sheet pile or the quality of the images on the sheets in the stack can be avoided.
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The three sheets are transported by the oscillation roller pair 127 and the reverse roll 130 and slide, as in 28A and 28B ge shows down on the processing tray 129 until they pass through the stop 131 be recorded. During this process, the stack tray is lowered once so that the upper surface of the sheet pile is lower than the sheet surface detection lever 133 , and then raised again. Lifting the stacker tray 128 is stopped when the sheet surface detection lever 133 is actuated by the upper surface of the sheet pile. Thus, the upper surface of the sheet stack on the stack tray 128 held at a predetermined height. From then on, the sheets are sequentially placed on the processing tray 129 stacked without on the lower transport guide plate 123b to be stored. When the number of stacked sheets on the processing tray 129 reaches a predetermined value, they are stacked. During the stapling operation, the first three sheets of the next sheet stack become on the lower transport guide plate 123b stored.
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Although the above description has been made with reference to the case in which three sheets on the lower transport guide plate 123b The number of intermediate sheets (ie, the buffer sheets) is not limited to three, but may be varied depending on the length of the sheets, the time required for the stapling operation, the sheet transport speed, or other factors.
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As described above, the sheet processing apparatus is 119 According to this embodiment, constructed in such a manner that in the in 26A shown state, the forward edge Pa of the sheet pile P protrudes beyond the forward edge P3a of the third sheet P3 by the length L. The reason for this structure will be described below. In connection with this, it should be noted that the forward facing edges P1a and P2a are located at a position above the forward edge P3a of the third arc P3.
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Assuming that the protruding length of the forward edge of the sheet stack P is L1 less than L, the projecting length of the backward edge of the third sheet P3 is also L1. Therefore, the length of the section at which the three buffer arches through the Oszillationswalzenpaar 127 are held after the sheet stack P on the stack tray 128 was ejected, briefly and the oscillation roller pair 127 could fail to hold the three buffer sheets. Therefore, the three buffer sheets can not reliably be sent to the processing tray 129 be delivered. In view of this, the apparatus is formed such that the sheet stack P protrudes beyond the forward edge P3a of the sheet P3 by the length L, so that the buffer sheets reliably through the pair of oscillation rollers 127 is held, so as to the processing tray 129 to be delivered.
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In addition, when the above-mentioned protruding length is short, the contact surface of the buffer sheets and the sheet stack is elongated, with the sheet stack being in close contact with the buffer sheets, so that the sheet stack falls on the stack tray 128 can be delayed. In this case, if the rotation of the oscillation roller pair 127 is turned over to the buffer sheets for processing 129 while conveying the sheet stack into the oscillation roller pair while adhering closely to the buffer sheets 127 occur, which could damage the sheet stack or cause a paper jam. In view of this, the apparatus is formed such that the sheet stack P protrudes beyond the forward edge P3a of the sheet P3 by the length L, so that the releasability of the sheet stack and the buffer sheets can be improved.
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According to the above-described, the device is formed in such a manner that the sheet stack, after being on the first sheet stacking device, in the form of z. B. the processing tray 128 , was stacked by the second sheet transport device, in the form of z. B. the trailing edge assistant 134 in the direction of the second sheet stacking device, in the form of z. B. the processing tray 128 is transported by a predetermined amount, wherein the by the sheet holding device in the form of z. B. the buffer unit 140 held buffer sheets P1, P2 and P3 and on the processing tray 129 stacked sheets simultaneously through the first sheet transport device in the form z. B. the Oszillationswalzenpaares 127 be transported so as to the stack tray 128 to be expelled. Consequently, the overlapping area of the sheet stack and the buffer sheets is reduced by an amount corresponding to the predetermined transport amount (ie, the length L) of the sheet stack, therefore, the sheet stack can be reliably separated from the buffer sheets and ejected for reliable stacking on the stack tray ,
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Furthermore, the sheet processing apparatus is formed in such a manner that the trailing edge of the sheet stack by the trailing edge assistant 134 is pushed. In the case that the trailing edge of the sheet stack by the trailing edge assistant 134 is pushed to be transported as above, the sheet can be transported reliably without damaging the surface of the sheet, in contrast to the case in which the sheet is transported and ejected by a rotating roller, which is brought into pressure contact with the surface of the sheet pile.
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In particular, in the case that the sheet stack, as in 30 shown only by the oscillation roller pair 127 is ejected, the sheet transport amount is likely to change depending on differences in the friction against the sheet or the rotational speed between the upper roller 127a and the lower roller 127b so that a shift between the upper part and the lower part of the sheets may occur. If this happens, there could be a slip between the pair of oscillation rollers 127 and the bow causing damage to the bow. In addition, the sheet pile could be twisted as a whole while ejecting. In this case, the stack of sheets can not be ejected uniformly and the processing time is prolonged. Further, when the sheet stack is twisted as a whole, there is a risk that the sheets will tear at the stapled portion, so that they become unusable.
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The above-mentioned incidents occur with great certainty when the sheet stack holding pressure of the oscillation roller pair 127 is increased in view of the reliable ejection of the sheet pile. In contrast, when the holding pressure is reduced, it is not possible to reliably transport the sheet stack. Therefore, it is difficult to maintain the holding pressure of the oscillation roller pair 127 suitable to adjust.
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In view of the above, the sheet processing apparatus is constructed such that the sheet stack not only by means of Oszillationswalzenpaares 127 is ejected, but also by means of the trailing edge assistant 134 , In this way, the above-mentioned slippage of the rotating roller against the sheet or the twisting of the sheet stack can be avoided, so that the sheet stack is ejected smoothly and quickly without damaging the sheets or the sheet stack. In addition, the sheet stack can be ejected without the need for accurate control of the holding pressure of the oscillation roller pair 127 ,
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Although the above description of the sheet processing apparatus has been given with reference to the case where the buffer unit 140 has been provided for storing (or buffering) a plurality of sheets in a straight condition during operation of the stapler 132 For example, the present invention can be applied to a device as in 31 Shown with a buffer roll unit, which is a buffer roll 13 and a buffer roll path. Therefore, the present invention is not limited to the sheet processing apparatus provided with a buffer unit 140 which is adapted to buffer a plurality of stacked sheets in a straight state (or to buffer).
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Although in the above description reference has been made to a case where the sheet position is detected by a sensor, the sheet position may be determined based on sheet storage information (storage information) stored in the CPU 221 be monitored.
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In addition, although the above sheet processing apparatus 129 is adapted to staple the sheet stack after the trailing edge orientation and width alignment for aligning the sheet stack has been performed from both sides, the sheet stack right after the width alignment and trailing edge alignment on the stack tray 128 be ejected without being stapled.